Promazone(TM) Outdoor Yard Solar Ultrasonic Mole Gopher Rodent Pest Repeller, 2 Count Work by emitting sonic pulses and vibrations which moles, voles, mice feel as a vibration transmitted through the ground. they then perceive a danger zone causing them to evacuate the area Transmitting ultrasonic waves 4-second pulse at 40-second intervals, the Solar Mole Repeller is effective within an area of 500 square meters Powered by a solar cell, no need for extra batteries. Please Choose the best sunshine location, so the solar panel to can receive the sunlight as directly as possible This item don't have any effect on children and pets. Easy and safe to use. No Poison, No Chemical Suitable for garden, aviary, farm yard or orchard ect. Used for: Chipmunks, Skunks, Raccoons, Groundhogs, Mice and other burrowing pests